In 2019, I was a CTO in a room with three people: the CEO, the CFO, and a stack of slides.
I had come to ask for a quarter of refactoring budget. Not a new feature. Not a migration. Just time — paid time — for my engineers to untangle a section of the platform that was quietly burning hours every sprint.
I had what I thought was a solid case. SonarQube scores were dropping. Story points per feature were trending up. The team had started using the word "frustrating" in every retrospective.
The CFO listened. She nodded. She pulled out a pen.
Then she asked: "How much will this save us next year?"
The silence that followed
I didn't have an answer.
I had a score. I had an intuition. I had an anecdote about a bug that had taken three days instead of an hour. What I didn't have was a number. A euro number. The kind that goes into a spreadsheet and comes out as an approved budget.
The budget was denied. We shipped anyway. The debt accumulated. Two years later, the same problem cost us three times more to address.
What engineering leaders are missing
Here is what I've learned in the years since that meeting:
- Every engineering leader I've met knows their tech debt is expensive.
- Almost none of them can put a number on it that their finance team will accept.
- The tools we have — SonarQube, Code Climate, Coverity — are built for engineers. They speak to developers, not decision makers.
The gap between what we know about our codebase and what we can prove to the people writing the checks is the single largest source of under-investment in software quality. It's not because CFOs are short-sighted. It's because we, as engineering leaders, have never figured out how to translate.
DebtLens is the translator
DebtLens reads your Git history. Not your source code. Your behavior. How often files change. Who changes them. What kinds of commits you produce — features, bug fixes, refactoring. Whether AI is writing parts of your codebase and whether those parts are being reviewed.
Then it multiplies these signals by the one thing every CFO already knows: the fully-loaded daily cost of a software engineer in Europe.
The output is three numbers in euros:
- Firefighting cost: what you burn reacting to bugs each month.
- Debt servicing: what you spend maintaining debt without reducing it.
- Recovery investment: the one-time cost to clean it up.
A CFO can approve that. A CFO can compare that to any other line item. A CFO can put that in a forecast.
The tool I wish I had
DebtLens is, very literally, the tool I wish I had walked into that meeting in 2019 carrying. The CFO would have read the number. The budget would have been approved. Or denied for reasons that had nothing to do with my inability to quantify the problem.
Either outcome would have been better than what actually happened.
If you are an engineering leader and you have ever left a budget meeting feeling like you should have been able to explain things better — this tool is for you.
I built it so the next CTO in that room has a better answer than I did.
— Jean-Marc